Methods of applying an adhesive or sealant material to a certain area, such as an edge, of a frame, such as a window frame, are well known. For example, there is a hand or manual method were the user manipulates the applicator device by pressure to dispense the material while moving the applicator along the frame using the senses of touch and feel. However, such a method is not automatable and relies on the operator to maneuver the applicator against the frame at whatever chosen dispensing pressure.
An apparatus of the prior art may employ an interpolation of X and Y speed references through an encoder for determining the speed and movement of a fluid dispenser, but does not employ a rotating nozzle or tubing member.
An apparatus of the prior art may employ robotics or machines that move in an X-Y orientation to move along the side and end members of the frame, but such machines and robotics do not detect for or account for irregularities, such as bowing of the frame member inwardly or outwardly, when dispensing the fluid material.
There are optical sensor systems that look for the corners of a frame to maneuver the applicator along the 90 degree turn in the frame, but the methods and apparatuses of the prior art have multiple operational problems with optical sensing of the members and corners of frames due to color, sheen, backgrounds, sensor adjustments, and others, which can result frequently in the breaking of nozzles.
There has been provided in the past the addition of “dumb” compensating devices that follow inconsistencies in a frame member but do not provide electrical feedback to a controller.
A method of the prior art is believed to force a member of a frame that is bowed, into fixtures to align the members with a predetermined path. There are also systems that look at the frame members' positions using a camera, and then create a path along which the applicator follows that particular frame member's position. These systems have problems with large views such as found in typical windows and doors.
Hand assist glazing tables are known, whereby a window frame is clamped to a table framework in a horizontal or vertical (art easel fashion) position. The framework supports a gantry slide system that is responsible for hand moving a dispensing valve with an extended non-rotating dispensing nozzle inside, against and around the inner portions of the vertical and perpendicular legs of a window frame of any shape. The inertia of the moving dispensing gantry can be significant, and the pressure exerted against the frame is operator-dependent. The non-rotating nozzle, along with the significant operator-created force and inertia of the dispensing valve, and various frictional forces exerted by the side edge of the frame against the nozzle, can result in marring or damaging the frame as well as damaging the nozzle. In order to maintain a consistent volume of dispensed sealant or adhesive material, the X and Y linear encoder frequencies are interpolated to determine the vector speed of the nozzle in any direction. This information is used to control a metering pump to produce a similar volume of dispensed material regardless of line speed. Due to the nature of the dispensed material, the start and stop volumes in the corners have separate adjustment.
Automated tracing tables move the nozzle automatically by motors and drives similar to hand glazing but have stopping points that generally do not touch the frame and are limited to rectangular shapes. Therefore bowed and “out-of-square” frames have dispensed adhesive or sealant material that can be dispensed at different distances from the ledge of the frame. It is known to use a spring-loaded nozzle compensator that enables a non-rotating dispensing nozzle to ride against the frame of slightly bowed or “out-of-square” windows. This compensator is very limited in performance due to the size and resulting design.
Automated glazing tables with dispensing recipes are known that are similar to the automated table above except they follow a predetermined path as chosen by a particular program recipe or from a barcode reading. The accuracy of the dispensed material is determined by the accuracy of the frame and/or the ability to fixture the frame into the predetermined path.
There remains a need for a method to follow the frame by touch with an automated prescribed pressure while applying a consistent volume of an adhesive or sealant to the surface of a frame member that is irregular in shape, form, or size.